The two Navy aircraft I flew, the F/A-18A and the F-14A, both had a system similar to the A4G. I very seldom had problems and those were mainly having my ears “pop” sometime after flight.
I never really understood why the US Navy did not use the diluter demand system type system. I believe I was told at one time that they used the constant O2 without dilution because of the ability to breathe in the water after ditching. I find that hard to believe as both the above aircraft had a small emergency oxygen bottle as part of the ejection seat which would have been available for those circumstances.